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using System;
using Xamarin.Forms;
using System.Collections.Generic;
using System.Collections.ObjectModel;
namespace Xamarin.Forms.Controls
{
public class ListRefresh : ContentPage
{
public ListRefresh ()
{
var refreshingCount = 0;
var grid = new Grid ();
var fooViewModel = new FooViewModel ();
var lv = new ListView {BindingContext = fooViewModel, IsGroupingEnabled = true, GroupDisplayBinding = new Binding ("Name"), IsPullToRefreshEnabled = false};
var stack = new StackLayout ();
var btn = new Button { Text = string.Format ("IsRefreshing {0}", lv.IsRefreshing) };
btn.Command = new Command (s => {
lv.IsRefreshing = !lv.IsRefreshing;
btn.Text = string.Format("IsRefreshing {0}",lv.IsRefreshing);
});
var btn4 = new Button { Text = "BeginRefresh", Command = new Command (s => {
lv.BeginRefresh();
btn.Text = string.Format("IsRefreshing {0}",lv.IsRefreshing);
}) };
var btn1 = new Button { Text = "EndRefresh", Command = new Command (s => {
lv.EndRefresh();
btn.Text = string.Format("IsRefreshing {0}",lv.IsRefreshing);
}) };
var btn2 = new Button { Text = string.Format ("Pull {0}", lv.IsPullToRefreshEnabled) };
btn2.Command = new Command (s => {
lv.IsPullToRefreshEnabled = !lv.IsPullToRefreshEnabled;
btn2.Text = string.Format("Pull {0}",lv.IsPullToRefreshEnabled);
});
var btn3 = new Button { Text = string.Format("CanExecute {0}",fooViewModel.CanExecute) };
btn3.Command = new Command (s => {
fooViewModel.CanExecute = !fooViewModel.CanExecute;
btn3.Text = string.Format("CanExecute {0}",fooViewModel.CanExecute);
});
var lbl = new Label { Text = string.Format ("Refreshing {0}", refreshingCount) };
lv.Refreshing += (object sender, EventArgs e) => {
refreshingCount++;
lbl.Text = string.Format ("Refreshing {0}", refreshingCount);
};
stack.Children.Add (btn);
stack.Children.Add (btn4);
stack.Children.Add (btn1);
stack.Children.Add (btn2);
stack.Children.Add (btn3);
stack.Children.Add (lbl);
lv.Header = new ContentView { HeightRequest = 300, HorizontalOptions = LayoutOptions.FillAndExpand, Content = stack };
lv.SetBinding<FooViewModel> (ListView.ItemsSourceProperty, m => m.Things);
lv.SetBinding<FooViewModel> (ListView.RefreshCommandProperty, m => m.RefreshThingsCommand);
grid.Children.Add (lv, 0, 0);
Content = grid;
}
public class FooViewModel
{
List<Group<string>> _things;
public List<Group<string>> Things {
get
{
return _things ?? (_things = new List<Group<string>> {
new Group<string>(new []{"A","B","C","D","E","F","G","H","I","J","K"}) {Name = "Letters"},
new Group<string>(new []{"1","2","3","4","5","6","7","8","9","10"}) {Name = "Numbers"}
});
}
}
bool _canExecute;
public bool CanExecute {
get
{
return _canExecute;
}
set {
_canExecute = value;
RefreshThingsCommand.ChangeCanExecute ();
}
}
Command _refreshThingsCommand;
public Command RefreshThingsCommand {
get {return _refreshThingsCommand ?? (_refreshThingsCommand = new Command (BeginRefreshThings, () => _canExecute ));}
}
protected void BeginRefreshThings()
{
}
}
public class Group<T> : ObservableCollection<T>
{
public Group (IEnumerable<T> seed) : base(seed){}
public string Name {
get;
set;
}
}
}
}
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